EPR, ENDOR and optical spectroscopy of Yb3+ ion in KZnF3 single crystals

Abstract The paramagnetic center of tetragonal symmetry formed by the Yb 3+ ion in the KZnF 3 crystal has been studied using methods of EPR, ENDOR and optical spectroscopy. The location of the impurity ion and the structural model of the complex differing from the model of the Yb 3+ center in KMgF 3 have been established. The empirical scheme of the energy levels of the Yb 3+ ion has been found. The parameters of its interaction with the crystal electrostatic field and the hyperfine interaction with ligands of the nearest environment have been determined. The parameters of the crystal field were used for the analysis of the distortions of the crystal lattice in the vicinity of Yb 3+ . The parameters of the transferred hyperfine interaction have been calculated for the distances between Yb 3+ and F − ions of the nearest environment obtained taking into account the found distortions. They are in good agreement with the experimental values.